Scientists have harvested the first vegetables grown in the EDEN-ISS greenhouse at Germany's Neumeyer-Station III in Antarctica. 3.6 kg of salad greens, 18 cucumbers, and 70 radishes were grown inside the greenhouse, which uses a closed water cycle with no soil.
An air management system controls the temperature and humidity, removes contaminants (such as ethylene, microbes, and viruses) and regulates the amount of oxygen and carbon dioxide to optimize growth. Water-cooled LEDs deliver lighting with a spectrum that is 15% blue (400-500 nm), 10% green (500-600 nm), ~75% red (600-700 nm), and ~2% far-red (700-750 nm). A nutrient delivery system stores stock solutions, acids/bases, deionized water, and nutrient solution, and pumps them into the cultivation system as needed.
The final crop yield for the shipping container sized facility is estimated to be 4.25 kg per week (250g each of lettuce, chard, rugula, and spinach, 1 kg of tomatoes, 600g of sweet peppers, 1 kg of cucumbers, 250g of radishes, 100g of strawberries, and 300g of herbs). The purpose of the project is to test food production technologies that could be used on the International Space System, Moon, Mars missions, etc. It will also provide fresh food supplementation year-round for the crew of Neumeyer-Station III (estimated population of 9 in the winter, 50 in the summer).
EDEN-ISS has some advantages (open, DOI: 10.5281/zenodo.60431) (DX) over the ISS's current Veggie system, including a higher available growth surface, longer possible production cycle using complete nutrient solution circulation, better reliability and safety, and the ability to grow taller crops (up to 60 cm). The system is designed to be flown to the ISS as a payload of EDR II experimental inserts.
Related: Tomorrow, NASA Astronauts Will Finally Eat Fresh, Microgravity-Grown Veggies
SpaceX Launches CRS-14 Resupply Mission to the ISS (carried the competing Passive Orbital Nutrient Delivery System)
(Score: 2) by takyon on Friday April 06 2018, @09:01AM (7 children)
Food is grown inside an enclosed environment on the ISS, just like it would be on the Moon. On the ISS, you have to bring over all your water and nutrients to grow anything, not just potassium and sodium. The Moon has greater exposure to radiation than the ISS, but that is a problem that will have to be solved anyway if you want astronauts to live there. That could mean going a few feet underground and using compressed regolith as natural shielding.
Perchlorate [wikipedia.org] may be a resource (rather than purely a nuisance/contaminant) with some Mars-relevant applications:
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 3, Informative) by c0lo on Friday April 06 2018, @12:43PM (6 children)
Look, I'm not saying it's impossible, I'm saying it's not straight-forward to use-the-regolith-as such-just-add-water.
In regards with perchlorates - yes, they are a source of oxygen when heated.
It would be very nice to have ammonium perchlorate on Mars, that would be a cheap source of ammonia. Unfortunately, ammonia and ammonium ion aren't very stable when bombarded with radiation - the nitrogen in the N2 molecule is so much stable (at lower energy) than in ammonia that the most economic way of producing ammonia consumes up to 5% of the world's annual natural gas production to make hydrogen and generate heat to run the reaction, and it consumes about 2% of the world's annual energy production. [stanford.edu]. So no, not ammonium perchlorate on Mars.
The perchlorate there is calcium perchlorate (almost 1% of the Martian dust, by weight) [wikipedia.org] - need to heat it over 400C [usra.edu] (PDF warning) to free the oxygen in the absence of catalysts, but will decompose quite easily (one would say too easily - may be explosively so) in the presence of iron oxides - Mars is not lacking of those.
And that sounds as bad luck [nature.com] for bacteria survival on Mars
So, add water and, without UV, calcium perchlorate will decompose and release oxygen to kill the bacteria or plants. With UV (to move the balance of the equation to favour chlorate production), it's deadly.
The solution: bring regolith inside, slowly add water and let the perchlorate decompose. Then add more water to wash out the remaining calcium chloride, because too much chlorine ions will kill your plants otherwise (Treated pool water damages the plants [sfgate.com] and guess what remains in the water after all the calcium hypochlorite does its job?)
One will have to hope they'll find enough water around on Mars.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by takyon on Friday April 06 2018, @01:02PM (5 children)
There seems to be an abundance of water on the Moon and Mars, and it could be decently accessible on Mars:
NAU planetary scientist’s study suggests widespread presence of water on the Moon [nau.edu]
Steep Slopes on Mars Reveal Structure of Buried Ice [soylentnews.org]
100 meter thick ice is under only 1-2 meters of dirt in some parts of Mars [nextbigfuture.com]
Hopefully, colonies would be very frugal and reuse as much waste as possible, keeping most of the obtained water cycling throughout the habitat.
Incidentally, there appears to be a lot of water at Mercury's poles [brown.edu]. Given Mercury's high gravity (0.38g, basically identical to Mars), and proximity to the Sun (about 6.5x greater power per solar panel than on Earth), it may be the better choice for a small colony.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by c0lo on Friday April 06 2018, @01:50PM (4 children)
I wouldn’t like to be there during solar storms.
Bremsstrahlung radiation from those energetic charged particle and huge flux values must be horrendous.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by GreatAuntAnesthesia on Friday April 06 2018, @03:37PM (3 children)
Mercury is tidally locked. One side is insanely hot and bathed in solar radiation, the other side is permanently in shadow and cold.
Any colony would most likely be built on the terminator between these two extreme environments. That way you could benefit from both: Solar panels on the hot side, sending their output via cables running a few tens of kilometres to the habitats which would be entirely or mostly in the shade, shielded from the sun's glare and lit by artificial light.
Alternatively, you could build on the shady side, near the terminator, and then build mirrors on very tall towers that peek over the horizon to reflect life-giving sunlight (but not the deadly radiation) down onto your colony. The mirrors could even be angled to "on" and "off" positions regularly to simulate a human & plant-friendly day / night cycle.
(Score: 2) by GreatAuntAnesthesia on Friday April 06 2018, @03:45PM
Scrap that last comment: I was wrong, Mercury isn't tidally locked at all. It rotates, albeit very very slowly.
(Score: 2) by takyon on Friday April 06 2018, @03:50PM
https://www.universetoday.com/130109/how-do-we-colonize-mercury/ [universetoday.com]
https://commons.wikimedia.org/wiki/File:North_pole_of_Mercury_--_NASA.jpg [wikimedia.org]
You want to set up shop in the shaded polar region, which has evidence of water ice.
The Universe Today article suggests using satellites to gather solar energy and then beaming it down to the surface (or even to other parts of the solar system), but I assume you could just put panels on the surface and run transmission lines to the polar craters.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by c0lo on Friday April 06 2018, @04:03PM
Mercury has a 3:2 spin–orbit resonance. 3 days every 2 tears in Mercury terms.
A colony on the terminator will need to move some tens or hundred of metres/hour - too lazy to do the actual calculation, but I believe a speed achievable by a human walking (EVAs would be possible).
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford